Hi everyone,
My friend is having a problem with her 1998 XJ8. I don't know much about the car (I havent seen it yet, to be honest, and she isnt too helpful), but I know a lot about cars in general and know her car's symptoms pretty well.
Here are the critical data:
-She bought the car used, but it was stock.
-Two years ago, the AC stopped working. She stopped driving it for a bit and about nine months later, it was working again. When it was broken, nobody could diagnose why.
-Around the time the AC went out, a few electrical problems popped up.
-The door lock button would set off the alarm fairly consistantly, but not always when it was pressed. Example: She would press the button and the alarm would go off. Another time, she would press the button and the alarm would go off three or four hours later.
-The wipers would freeze intermittently.
-The car would not always start when the key was turned. If she turned it a few times, it would start. She said that moving the seat or wheel helped it, but I'm not sure I believe it really contributed.
-Now, she's got to drive the Jag again, and it's got a new problem. The car wouldn't start yesterday and the dealership had to jump it. It started fine, but whenever she pressed the door lock button (or unlock button, for that matter), the seat would recline! With every push, it leaned back further.

To me, it seems like one of two things... Either
a) The computer died, or
b) there is a short... somewhere.

Anyone here experience something like this? Tips, tricks? I've got about two days before I look at it, and one shot before she sells it to a dealer as a trade in. Help, please!
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This seems like the BPM (Body Processing Module) located behind the glove box. When this is not earth properly, some you the symptoms described by you could occur.
Try this, remove the glove box compartment (very easy, some few screws), locate the BPM and start to wiggle it and/or the main connector going into it while you observe if the red LED right next to the gear shifter comes on. If it does, you have an earth problem. This could either be in the connector or in the BPM itself. I had it in the BPM and had to open it up and resolder the two main earth points (which happens to be soldering over two screws holding the PCB to the frame of the BPM. Good luck!!